Silane can be produced from chlorosilanes including silicon tetrachloride. For example, the reaction of LiAlH.sub.4 with SiCl.sub.4 in an ether reaction medium is known to produce silane.
Alane, that is aluminum trihydride or AlH.sub.3, has in the past been produced from the reaction of LiAlH.sub.4 and AlCl.sub.3 in ethers. Also known is the production of an alane dimethyl ether solution from the reaction of LiH and AlCl.sub.3 in dimethyl ether, catalyzed by NaAlH.sub.4.
Amines are used to produce amine alanes for subsequent syntheses. For example, LiAlH.sub.4 can be reacted with a trialkyl amine.multidot.HCl complex to precipitate LiCl and form AlH.sub.3 .multidot.NR.sub.3 where R is alkyl.
The reaction of LiAlH.sub.4 with silicon tetrafluoride has been reported. Although the by-products of this reaction have not been described, it is believed that they would comprise complex lithium aluminum fluorides such as Li.sub.3 AlF.sub.6, Li.sub.5 Al.sub.3 F.sub.14, etc., along with some AlF.sub.3. Compared to AlF.sub.3, these lithium aluminum fluorides are low value materials of minimal utility.
My prior copending application Ser. No. 449,486 filed Dec. 13, 1982 describes an excellent process for the preparation of silane. In that process the by-products comprise a mixture of AlF.sub.3 and complex sodium aluminum fluorides.